Vacuum Sealing Appliance Including Vacuum Cycle With Transducer Feedback

ABSTRACT

A vacuum sealer apparatus includes a housing having a vacuum chamber therein, a vacuum pump in fluid communication with the vacuum chamber, a sealing mechanism adjacent a periphery of the vacuum chamber, and at least one processor. The at least one processor is configured to execute program code stored in a non-transitory computer readable storage medium to calculate a rate of change of a vacuum level in the vacuum chamber responsive to energizing the vacuum pump to withdraw air from the vacuum chamber, and to energize the sealing mechanism and/or reduce power to the vacuum pump based on the rate of change of the vacuum level. Related methods of operation are also discussed.

FIELD

The present invention relates generally to small appliances, and more particularly to vacuum sealer appliances.

BACKGROUND

Vacuum sealers are small appliances, generally utilized to vacuum (i.e., evacuate or otherwise withdraw air from) and seal polymeric or plastic vacuum bags (generally referred to herein as bags) containing foodstuffs for longer term storage while preserving freshness. Vacuum sealers may include a vacuum chamber and a vacuum pump for pumping air out of the open end of a bag, and an elongated heat sealing bar to seal the open end once the air has been pumped out of the bag.

The bags may be formed from a roll of bag stock that has two opposing side edges that are factory-sealed. A desired length of bag stock can be cut off the roll, such that the cut bag stock may have two opposing sealed side edges and at least one open end. Foodstuff items may be placed in the bag and the edge of the open end of the bag may be positioned within the vacuum chamber. The vacuum pump may be activated to create a vacuum in the vacuum chamber and the air may be vacuumed out of the bag. When the air has been evacuated from the bag, the open end of the bag may be sealed by the heat sealing bar.

When attempting to seal wet or moist items or liquids, some of the liquid in the bag might be vacuumed out of the bag along with the air. The escaping liquid is undesirable, as the liquid is pulled into the vacuum chamber (which can create a mess that is difficult to clean up), onto the sealing surface of the bag (which can prevent a good heat seal), and/or into the vacuum pump (which can damage the vacuum pump).

SUMMARY

According to some aspects, embodiments of the present invention are directed to a vacuum sealer apparatus. The vacuum sealer apparatus comprises a housing comprising a vacuum chamber therein; a vacuum pump in fluid communication with the vacuum chamber; a sealing mechanism adjacent a periphery of the vacuum chamber; and at least one processor. The at least one processor is configured to execute program code stored in a non-transitory computer readable storage medium to perform operations comprising: calculating a rate of change of a vacuum level in the vacuum chamber responsive to energizing the vacuum pump to withdraw air from the vacuum chamber; and energizing the sealing mechanism and/or reducing power to the vacuum pump based on the rate of change of the vacuum level.

According to some aspects, embodiments of the present invention are directed to a method of operating a vacuum sealer apparatus. The method comprises executing, by at least one processor of the vacuum sealer apparatus, program code stored in a non-transitory computer readable storage medium to perform operations comprising: calculating a rate of change of a vacuum level in a vacuum chamber having a vacuum pump in fluid communication therewith responsive to energizing the vacuum pump to withdraw air from the vacuum chamber; and energizing a sealing mechanism adjacent a periphery of the vacuum chamber based on the rate of change of the vacuum level.

According to some aspects, embodiments of the present invention are directed to a vacuum sealer apparatus. The vacuum sealer apparatus comprises a housing including a vacuum chamber therein, where the vacuum chamber is configured to receive an open end of a polymeric bag adjacent a periphery thereof; a vacuum pump in fluid communication with the vacuum chamber; a sealing mechanism including at least one heating element adjacent the periphery of the vacuum chamber; and at least one processor. The at least one processor is configured to execute program code stored in a non-transitory computer readable storage medium to perform operations comprising: calculating a rate of change of a vacuum level in the vacuum chamber responsive to energizing the vacuum pump to withdraw air from the vacuum chamber; identifying a transition in the rate of change of the vacuum level in the vacuum chamber, where the transition indicates substantial removal of air from the polymeric bag without substantial removal of fluid from the polymeric bag; and energizing the at least one heating element and reducing power to the vacuum pump responsive to identifying the transition in the rate of change of the vacuum level.

Other apparatus and/or methods according to embodiments of the present invention will become apparent to one with skill in the art upon review of the following drawings and detailed description. It is intended that all such additional embodiments, in addition to any and all combinations of the above embodiments, be included within this description, be within the scope of the invention, and be protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front, top perspective view of a vacuum sealer, with the lid closed, according to some embodiments of the present invention.

FIG. 2 is a front, top perspective view of the vacuum sealer of FIG. 1, with the lid open.

FIG. 3 is a front, top perspective view of a vacuum sealer, according to further embodiments of the present invention.

FIGS. 4A and 4B are top plan views of exemplary vacuum bags according to some embodiments of the present invention.

FIG. 5 is a block diagram illustrating an exemplary electronic architecture of a vacuum sealer according to some embodiments of the present invention.

FIG. 6 is a block diagram illustrating an example of the processor and memory of FIG. 5.

FIG. 7 is a graph illustrating an exemplary vacuum cycle for a vacuum sealer in evacuating air from a vacuum bag according to some embodiments of the present invention.

FIGS. 8 and 9 are flowcharts illustrating exemplary operations of a vacuum sealer in evacuating air from a vacuum bag according to some embodiments of the present invention.

DETAILED DESCRIPTION

The present disclosure now is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

In the figures, certain layers, components or features may be exaggerated for clarity, and broken lines illustrate optional features or operations unless specified otherwise. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention. The sequence of operations (or steps) is not limited to the order presented in the claims or figures unless specifically indicated otherwise.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and/or clarity.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

Some embodiments of the present invention may arise from recognition that, in a vacuum sealer that can evacuate air from and seal vacuum bags containing fluids (e.g., liquid contents and/or wet or moist items), the rate at which the fluids are evacuated from the bag may begin to change once the air has been substantially removed from the bag. More particularly, embodiments of the present invention are directed to identifying an inflection point indicating when substantial removal of the air from a vacuum bag has occurred without substantial removal of fluid in the vacuum bag, by comparing the rate of change of vacuum data (indicating the vacuum level in the bag and/or vacuum chamber) during the evacuation of the air from the bag. As used herein, “vacuum level” may refer to a difference in pressure between atmospheric pressure and the pressure in the evacuated chamber or bag. In some embodiments, one or more processors associated with the vacuum sealer may execute program code to calculate a slope of a signal indicating the vacuum level in the vacuum chamber, identify a transition in the slope from decreasing (negative slope) to increasing (positive slope) as the inflection point, and begin sealing the bag and/or decreasing the suction provided by the vacuum pump in response to identifying the transition, so as to reduce or prevent fluid in the bag from being pulled into the vacuum chamber.

FIG. 1 is a front, top perspective view of a vacuum sealer device or apparatus (also referred to herein as a vacuum sealer), with the lid closed, according to some embodiments of the present invention. FIG. 2 is a front, top perspective view of the vacuum sealer of FIG. 1, with the lid open. Referring now to FIGS. 1 and 2, the vacuum sealer 10 includes a housing 11 with an upper portion 14 and a lower portion 12 that is adapted to rest on a support surface (such as a countertop) during use. The lower portion 12 has a top surface 13, as shown in FIG. 2. The upper portion 14 includes a user interface or control panel 16 that is configured to receive inputs from a user to control operations of the vacuum sealer 10. The vacuum sealer 10 also has a lid 18 pivotably attached to the housing 11. The lid 18 is movable between a closed position (seen in FIG. 1) in which the lid 18 is covering at least a portion of the top surface 13 of the lower portion 12, and an open position (seen in FIG. 2) that exposes the top surface 13 of the lower portion 12. The lid 18 may be supported by opposing arms 20 pivotably attached to the lower portion 12. The top surface 13 of the lower portion 12 defines a first cavity 15 and the lid 18 defines an opposing second cavity 17 in an underside of the lid 18. The first cavity 15 and the second cavity 17 together in the closed position of the lid 18 form a sealed vacuum chamber 26 therebetween.

The control panel 16 includes one or more input elements (buttons, switches, knobs, etc.) and/or one or more output elements (alphanumeric displays, lights, buzzers, etc.). In some embodiments, the control panel 16 may include a touchscreen display that provides both input and output elements. A sealing mechanism (illustrated as a sealing bar) 22 is secured on the underside of the lid 18, although it could be located in the lower portion 12 or other suitable location adjacent a periphery of the vacuum chamber 26. The sealing bar 22 may include one or more heating ribbons that heat up when electricity is applied (also referred to herein as energizing or energization) during a sealing operation to heat seal an opening of a bag. The corresponding top surface 13 of the lower portion 12 may have a thermally insulating backing strip 24 that is positioned such that a bag is sandwiched between the sealing bar 22 and the thermally insulating backing strip 24 when the lid 18 is in the closed position. In an alternate embodiment, the thermally insulating backing strip 24 is located in the lid 18, while the sealing bar 22 is located in the corresponding top surface 13 of the lower portion 12 of the housing 11.

The vacuum chamber 26 is configured to seal around the open end of a polymeric or plastic bag (such as the bags shown in FIG. 4A or 4B) when the lid 18 is in the closed position. During operation of the vacuum sealer 10, air is vacuumed out of the vacuum chamber 26, which in turn vacuums air out of the interior of the bag via the open end. A vacuum pump 21 (shown in phantom line in FIG. 2) is housed inside the housing 11, and is in fluid communication with the vacuum chamber 26 to withdraw air from the vacuum chamber 26 and create a vacuum therein when energized by a power supply 19 (shown in phantom line in FIG. 2). The sealed vacuum chamber 26 is configured to hold the open end of the bag between the first and second cavities 15, 17, as the power supply 19 energizes the vacuum pump 21 to withdraw air from the bag. A latch 28 is provided to secure the lid 18 in the closed position during operation of the vacuum sealer 10. In some embodiments, the suction provided by the vacuum pump 21 may be sufficient to hold the lid 18 in the closed position during operation to maintain the seal between the first and second cavities 15, 17 of the vacuum chamber.

The vacuum chamber 26 may include one or more sensors 36 (shown in phantom line in FIG. 2) that are configured to output respective signals that can be converted to or are otherwise indicative of a vacuum level in the vacuum chamber 26. For example, the sensor(s) 36 may include a current sensor that is electrically coupled to the vacuum pump 21, and/or pressure transducer that is positioned in the vacuum chamber 26 or is in fluid communication with the vacuum chamber 26 (e.g., mounted to a printed circuit board that is connected to the vacuum chamber 26 by a port). The current sensor 36 may be configured to output a signal indicative of the current draw responsive to operation of the vacuum pump 21. The pressure transducer 36 may be configured to output a voltage signal based on the vacuum level in the vacuum chamber 26 responsive to operation of the vacuum pump 21. As described below, one or more processors associated with the vacuum sealer 10 may execute program code to convert the output signals from the sensor(s) 36 into a vacuum level signal or data, and may control operation of the sealing mechanism 22 and/or the vacuum pump 21 based on the rate of change of the vacuum level.

The sealing mechanism or bar 22 may include a heating ribbon or other heating element having one or more segments along a length of the sealing bar 22, which may correspond to a dimension of the open end of a vacuum bag. With multiple segments, the segments may be activated serially or in parallel to seal different portions of the open end of a bag at different times, e.g., such that a portion of the open end of the bag can be initially sealed and the remainder of the open end of the bag can be subsequently sealed. For example, some embodiments may begin sealing a portion of the bag by activating one or more of the heating ribbon segments before or as the vacuum pump 21 is energized to withdraw air from the bag, and may begin sealing a remaining portion of the bag (for instance, a shorter portion) by activating one or more of the remaining heating ribbon segments responsive to identifying the transition in the rate of change of the vacuum level as described herein to complete the sealing. That is, the heating element may include multiple segments, which may be energized in sequence responsive to identifying the transition. Ends of the sealing bar 22 may be electrically connected to the power supply 19 to provide electricity to the heating ribbon(s). The electrical connection at one or more ends of the heating ribbon may be spring-loaded to allow the ribbon to expand/contract during heat cycling.

FIG. 3 is a front, top perspective view of a vacuum sealer 110 according to further embodiments of the present invention, which may provide improved positioning of a bag for vacuuming and sealing as the lid is closed. The lid is removed in FIG. 3 to more clearly illustrate the mechanism for improved bag positioning. As shown in FIG. 3, the vacuum sealer 110 includes a housing 11 with a lower portion 112 adapted to rest on a support surface (such as a countertop) during use, an upper portion 114, a control panel 116, and a lid. A vacuum chamber 126 seals around the open end of the bag when the lid is in the closed position. A sealing bar is positioned on the underside of the lid, so as to be positioned adjacent a periphery of the vacuum chamber 126 when the lid is in the closed position. The top surface of the lower portion 112 has a thermally insulating backing strip 124 that is positioned such that a polymeric or plastic bag is sandwiched between the sealing bar and the thermally insulating backing strip 124 when the lid is in the closed position. In an alternate embodiment, the thermally insulating backing strip 124 is located in the lid, while the sealing bar is located in the corresponding top surface of the lower portion 112 of the housing. During operation of the device, air is vacuumed out of the vacuum chamber 126, which in turn vacuums air out of the bag via the open bag end.

The vacuum sealer 110 further includes a bag holding mechanism 130 that is affixed to or integral with the lower portion 112. The bag holding mechanism 130 includes a main body 132, having a first end 111 and a second end 113, affixed to the lower portion 112 via opposing end brackets 134. The bag holding mechanism 130 further includes two clamps for holding a bag in place, either of which may be fixed or movable in a lateral direction. For example, the first or right side clamp, which is part of a first latch mechanism 115 movably disposed on the first end 111 of the main body 132, may be movable laterally along a carriage 140 that slides along the main body 132 such that the distance between the first latch mechanism 115 and the second latch mechanism 117 can be adjusted. The second clamp, which is part of a second latch mechanism 117 disposed proximate to the second end 113 of the main body 132 in line with the first latch mechanism 115, may be fixed so as not to permit lateral movement. The first and second clamps 115 and 117 are pivotably mounted on respective mounts so as to be movable between respective open and closed positions, so as to retain a bag placed in a correct or desired position for vacuuming/sealing thereunder when in the closed positions. The first clamp 115 may be biased outwardly to apply tension to the bag to help remove wrinkles for better sealing of the bag.

In some embodiments, the vacuum sealer 10, 110 may further include a plastic roll compartment housing and storing a roll of plastic bag stock therein, from which the vacuum bags can be dispensed. For example, the plastic roll compartment may be is located within the lower housing 12 (e.g., accessible by a pivotable door) in order to accommodate/cradle the roll of plastic bag stock. The bag stock may have two opposing side edges that are factory sealed. A desired length of bag stock can be cut off the roll (for example, by a cutting mechanism in the plastic roll compartment), such that the cut bag stock defining the vacuum bag has two opposing sealed side edges, e.g., left and right sides, and at least one open end.

FIGS. 4A and 4B are top plan views of exemplary vacuum bags 80 a and 80 b (generally referred to herein as “80”) according to some embodiments of the present invention. Referring now to FIG. 4A, a polymeric bag 80 a has an open end 82 at which a seal 84 a, 86 a may be created by energizing the sealing mechanism 22 responsive to detection of a change in the vacuum level in accordance with embodiments described herein, thereby sealing contents of the bag 80 a in a portion 85. As shown in FIG. 4B, an alternate bag 80 b having an open end 82 including two parallel seals 84 a, 86 a and 84 b, 86 b that may be created by energizing the sealing mechanism 22 responsive to detecting a transition in the rate of change in the vacuum level in accordance with embodiments described herein. A portion of the seal(s) 84 a and/or 86 b may be created prior to energizing the vacuum pump 21, and a remaining portion 86 a and/or 84 b (as indicated by dashed lines) may be sealed responsive to responsive to detecting the transition in the rate of change of the vacuum level in some embodiments.

In operation, the vacuum pump 21 is energized by the power supply 19 to draw out air from the polymeric bag 80 via the open end 82 thereof and through the aperture within the vacuum chamber 26, 126. To seal the open end of the bag 80 (responsive to detecting the transition in the rate of change of the vacuum level), the sealing bar 22 including one or more heating ribbons is then energized for a prescribed time and/or to a prescribed temperature to seal the portion of the bag 80 pressed between the sealing mechanism 22 and the backing strip 24, 124.

FIG. 5 is a block diagram illustrating exemplary components 300 of an electronic architecture of a vacuum sealer apparatus, such as the vacuum sealer 10 of FIGS. 1 and 2 or the vacuum sealer 110 of FIG. 3, according to some embodiments of the present invention. The electronic architecture may include hardware, software implemented with hardware, firmware, tangible computer-readable storage media having instructions stored thereon and/or a combination thereof.

As illustrated in FIG. 5, the electronic components 300 include a processor circuit 340, a memory 330, a user interface 355, and one or more sensors 360 electrically coupled to the processor 340. The processor 340 may include or otherwise represent one or more microprocessors or microcontrollers that is/are configured to control operations of the device 300. The memory 330 may be a general purpose memory that is used to store both program instructions for the processor 340 as well as data, such as image data, configuration data, and/or other data that may be accessed and/or used by the processor 340. The memory 330 may include a nonvolatile read/write memory, a read-only memory, and/or a volatile read/write memory. For example, the memory 330 may include a read-only memory in which basic operating system instructions are stored, a non-volatile read/write memory in which re-usable data, such as configuration information, may be stored, as well as a volatile read/write memory, in which short-term instructions and/or temporary data may be stored. As such, the memory 330 can store computer readable program code or instructions that, when executed by the processor circuit 340, carry out operations described herein, such as the operations illustrated in the flowcharts of FIGS. 8-9. The memory 330 may also include systems and/or devices used for storage of data captured by the device 300, such as vacuum data as indicated by the output of one or more of the sensors 360.

The sensor(s) 360 may include any sensors that are configured to directly or indirectly measure pressure in the vacuum chamber 26, by providing data or signals indicative of the vacuum level in the chamber 26 to the processor 340. For example, the sensor(s) 360 may include one or more transducers, such as a pressure transducer that outputs a voltage signal from which the processor 340 can calculate pressure. The user interface 355 may include various input/output components, including a display 354, virtual and/or physical buttons 351, switches 356, and/or knobs 358. The user interface 355 may thus be configured for receiving user input, displaying operating status, and/or providing alerts or otherwise signaling malfunction to a user.

The electronic components 300 may further include one or more communication interfaces 345 that may communicate with other communication devices and/or one or more networks, including any conventional, public and/or private, real and/or virtual, wired and/or wireless network, including the Internet. The communication interfaces 345 may be used by the processor 340 to transfer information in the form of signals between the vacuum sealer and another computer (e.g., a smartphone or application executing thereon) or a network (e.g., the Internet), for example, to automatically submit a request to re-order vacuum seal bags responsive to detecting a low supply of the vacuum bags. In some embodiments the vacuum sealer 10, 110 may be configured for communication with other household devices in an Internet-of-Things (IoT) environment. The communication interfaces 345 may include a modem, a network interface (such as an Ethernet card), a wireless interface, a radio interface, a communications port, or the like.

FIG. 6 is a block diagram illustrating the processor 340 and memory 330 of FIG. 5 in greater detail. As shown in FIG. 6, the processor 340 and memory 330 are electrically coupled by an interconnect 310. The interconnect 310 may be an abstraction that represents any one or more separate physical buses and/or point to point connections, connected by appropriate bridges, adapters, or controllers. The memory 330 may include one or more storage repositories 334. The storage repository 334 may be accessible to the processor 340 via the system interface 310 and may additionally store information associated with the vacuum sealer 10, 110 and/or operations performed thereby responsive to execution of the computer readable program code/instructions 332. For example, in some embodiments, the storage repository 334 may contain vacuum level data that is derived from output signals from one or more of the sensors 360 of FIG. 5.

The processor 340 may be, or may include, one or more programmable general purpose or special-purpose microprocessors, digital signal processors (DSPs), programmable controllers, application specific integrated circuits (ASICs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), trusted platform modules (TPMs), or a combination of such or similar devices. The processor 340 may be configured to execute computer program code/instructions 332 stored in the memory 330. The computer program code/instructions 332 may represent one or more program modules that are executable to perform operations for controlling a vacuum sealer in evacuating air from a vacuum bag in accordance with some embodiments of the present invention.

In particular, the processor 340 may be configured to execute the program code 332 to convert a voltage signal output from a vacuum transducer 36 into a vacuum reading or level (in units of pressure, e.g., millimeters of mercury (mm-Hg)) indicating the pressure in the vacuum chamber 26, 126 (i.e., the pressure differential between the evacuated volume of the chamber 26, 126 relative to the surrounding atmosphere). The processor 340 may store samples or data points from this signal as vacuum level data in the storage repository 334 of the memory 330. By comparing the samples of the signal, the processor 340 may identify a transition in the vacuum level of the chamber where a rate of change between first or prior samples of the signal is greater than a rate of change between second or subsequent samples of the signal, and may use the identification of this transition as a trigger to energize the sealing mechanism and/or to de-energize (or reduce energization to) the vacuum pump 21.

FIG. 7 is a graph illustrating an exemplary vacuum cycle for operation of a vacuum sealer according to some embodiments of the present invention in sealing a vacuum bag. In particular, the graph of FIG. 7 illustrates a vacuum level 705 in the vacuum chamber 26 (e.g., as determined from signals output from one or more sensors 360), a slope 710 or rate of change at respective points of the vacuum level 705, and a current draw 715 of the vacuum sealer (e.g., of the vacuum pump 21 and/or the sealing mechanism 22) during a vacuum cycle in evacuating air from a vacuum bag that contains at least some liquid or fluid. The rate of change or slope 710 of the vacuum level 705 may vary based on the type and/or volume of the bag, and/or based on relative amounts of solid and liquid content in the bag. Embodiments of the present invention may recognize that the rate at which the liquid or fluid leaves a vacuum bag decreases at the point at which the air in the vacuum bag is substantially removed, and that this inflection point or transition can be determined from the rate of change of the vacuum level 705.

FIGS. 8-9 are flowcharts illustrating exemplary operations of a vacuum sealer in evacuating air from a vacuum bag in accordance with some embodiments of the present invention. The operations of FIGS. 8-9 may be performed by one or more processors, such as the processor 340 shown in FIGS. 5-6, responsive to execution of computer readable program instructions stored in a memory, such as the computer readable program code/instructions 332 stored in the memory 330 shown in FIGS. 5-6. The blocks of FIGS. 8-9 may thus define executable computer readable program code for controlling the respective operations illustrated therein.

As shown in FIG. 8, in a vacuum cycle of the vacuum sealer 10, 110, the vacuum pump 21 is energized at block 805 to evacuate air from a vacuum bag 80 having an open end placed in the vacuum chamber 26. For example, the vacuum pump 21 may be energized responsive to receiving a user input at the user interface 16, 355, responsive to detecting the presence of an end of a vacuum bag 80 in the chamber 26, 126, responsive to detecting closure of the lid 18, or a combination thereof. A rate of change in the vacuum level of the vacuum chamber 26, 126 (and the vacuum bag 80 having the open end placed therein) is calculated at block 825, for example, based on signals received from one or more of the sensors 360. Based on the rate of change calculated at block 825, a sealing mechanism 22 of the vacuum sealer 10, 110 is energized, and/or the energization to the vacuum pump 21 is reduced. More particularly, as noted above, a transition in the rate of change may indicate substantial removal of air from the vacuum bag. As such, calculating the rate of change at block 825 may include calculating the slope 710 of the vacuum level to identify this transition, which, as shown in FIG. 7, is the point 799 at which the slope 710 changes from decreasing in value (i.e., a negative slope) to increasing in value (i.e., a positive slope).

FIG. 9 illustrates operations for controlling the vacuum sealer 10, 110 in greater detail. As shown in FIG. 9, the vacuum pump 21 of the vacuum sealer 10, 110 is energized at block 905. For example, the processor 340 may be configured to energize the vacuum pump 21 by activating the power supply 19 responsive to receiving a user input via the user interface 16, 355. The processor 340 may receive a signal from at least one of the sensors 360 (e.g., a voltage signal from the pressure transducer 36) at block 910, and may convert the received signal into a vacuum level signal or data 705 (e.g., based on one or more parameters of the pressure transducer) for the vacuum chamber 26, 126 at block 915. The processor 340 may store multiple readings or data points from the vacuum level signal 705 in the storage repository 334 as vacuum data at block 920. For example, the processor 340 may sample the vacuum level signal 705 at a frequency of about 2 Hz, such that readings or data points from the vacuum level signal 705 are stored for 0.5 second intervals of the signal 705 (described in this example with reference to data points for the previous 0.5, 1, and 1.5 seconds of the vacuum level signal 705). The processor 340 may calculate the rate of change or slope 710 of the vacuum level signal 705 based on the stored data points at block 925. For example, the processor 340 may calculate the slope 710 based on the rate of change between first samples or data points for the previous 1 second and 1.5 seconds of the vacuum level signal 705, and between second samples or data points for the previous 0.5 second and 1 second of the vacuum level signal 705.

Still referring to FIG. 9, the processor 340 may identify an inflection point or transition 799 in the slope 710 of the vacuum level signal 705. In particular, at block 930, the processor 340 may identify the transition 799 when a second slope between second or subsequent data points is increasing or has a positive slope in comparison to a first slope between first or prior data points that is decreasing or has a negative slope. That is, calculating the slope 710 may include calculating first and second slopes for first and second samples of the vacuum level data, respectively, and identifying the transition 799 may include determining when the second slope between the second data points is greater than the first slope between the first data points. For example, the processor 340 may identify the transition 799 where the rate of change between a first subset of the stored data points (in this example, for the previous 1.5 to 1 second) is greater than the rate of change between a second subset of the stored data points (in this example, for the previous 1 to 0.5 seconds), indicating the transition 799 of the slope 710 from a negative slope (decreasing in value) to a positive slope (increasing in value).

The processor 340 may use detection of this instance or transition 799 as a trigger to energize the sealing mechanism 22 and/or to de-energize (or reduce energization to) the vacuum pump 21. In particular, responsive to identifying the transition 799 in the slope 710 where the second slope is increasing as compared with the first slope at block 930, the processor 340 may energize the heating element(s) of the sealer mechanism 22 to initiate the sealing process at block 935. At this time, the processor 340 may also de-energize or reduce the power to the vacuum pump 21 at block 940. If the transition 799 is not detected (that is, if the second slope is not determined to be increasing relative to the first slope at block 930), operations return to block 910 where the processor 340 receives the signal output from the sensor(s) 360 (e.g., the voltage signal output from the pressure transducer 36) so as to continue operations for monitoring the vacuum level in the vacuum chamber 26 in order to identify the transition 799.

In some embodiments, the processor 340 may stepwise or continuously decrease power to the vacuum pump 21 at block 940 responsive to detection of the transition 799 at block 930. For example, in some embodiments, the suction provided by the vacuum pump 21 may operate not only to evacuate the air from the vacuum bag 80, but also to maintain an airtight seal between the portions of the vacuum chamber 26, 126 defined by the upper cavity 17 (provided by the lid 18) and the lower cavity 15 (provided by the lower portion 12 of the housing 11). As such, the processor 340 may continue to operate the vacuum pump 21 (albeit at a reduced power level) responsive to identifying the transition 799 in the slope 710 of the vacuum level 705 to maintain pressure in the vacuum chamber 26 until or shortly after the sealing of the bag 80 is completed by the sealing mechanism 22, at which point the processor 340 may fully de-energize the vacuum pump 21.

As noted above, the signal(s) indicating the pressure in the vacuum chamber 26 may be received at block 910 from one or more sensors 360. In some embodiments, the sensor(s) 360 may include a pressure transducer 36, which may be located in or may be otherwise in fluid communication with the vacuum chamber 26, 126. For example, the pressure transducer 36 may be mounted in the vacuum chamber 26, 126, or on a circuit board that is outside of the vacuum chamber 26, 126, but is mechanically coupled to the vacuum chamber 26, 126 by a port and/or tube. The pressure transducer 36 may output a voltage signal responsive to actuation of the vacuum pump 21, and the processor 340 may convert or otherwise calculate the vacuum level 705 in the vacuum chamber 26 based on the voltage signal.

In some embodiments, the sensor(s) 360 may include a current sensor that is electrically connected so as to determine the current draw 715 of the vacuum pump 21 and/or the sealing mechanism 22. The increase in the current draw 715 shortly after the transition 799 in the slope 710 of the vacuum level signal 705, as shown in FIG. 7, may be responsive to the energizing of the heating element(s) of the sealing mechanism 22.

In some embodiments, the processor 340 may be configured to analyze the signals indicating the pressure in the vacuum chamber received from one or more sensors 360 for troubleshooting purposes. For example, the processor 340 may perform a calibration operation (e.g., without the presence of the vacuum bag 80) to determine a baseline pressure for the vacuum chamber 26, 126. If this baseline pressure is not subsequently achieved within a predetermined amount of time after energizing the vacuum pump 21 to evacuate air from an installed vacuum bag 80, the processor 340 may determine that the vacuum chamber 26, 126 and/or the bag 80 is leaking, or that the sealing of the vacuum chamber 26, 126 is otherwise compromised. As another example, the processor 340 may determine an atmospheric pressure of the operating environment when the vacuum chamber 26, 126 is open, and may correct or otherwise adjust calculation of the vacuum level based on the atmospheric pressure or an altitude indicated thereby, or may otherwise alter the operating cycle of the vacuum sealer 10, 110 based on the determined atmospheric pressure. In some embodiments, the altitude-compensated vacuum level may be used as a trigger to reduce power to the vacuum pump 21 and/or energize the sealing mechanism 22 when a predetermined vacuum level or difference in vacuum level has been achieved for bags containing primarily dry items or foodstuffs, in addition or alternatively to operating the vacuum pump 21 and/or heat sealing mechanism 22 responsive to determining the inflection point as described herein for bags containing moist or liquid items or foodstuffs. As the vacuum level inside a bag depends on the volume of air that is present in the bag (which may vary depending on many factors, such as bag size, food volume, etc.), the output signals from transducers or other pressure sensors may be thereby corrected so as to calculate a more accurate vacuum level for triggering the sealing mechanism 22 and/or vacuum pump 21 to provide more consistent results.

Embodiments of the present invention as described herein may thus reduce the likelihood of liquid escaping from a vacuum bag when the air is vacuumed out of the bag, by controlling sealing mechanism and/or vacuum pump operation based on the rate of change of the vacuum level in the vacuum chamber. Vacuum sealers in accordance with the present invention can accomplish the above and other objectives and thereby overcome at least the above-described disadvantages of some conventional vacuum sealers.

The flowcharts shown in the Figures illustrate the architecture, functionality, and operations of embodiments of hardware and/or software according to various embodiments of the present invention. It will be understood that each block of the flowchart and/or block diagram illustrations, and combinations of blocks in the flowchart and/or block diagram illustrations, may be implemented by computer program instructions and/or hardware operations. In this regard, each block represents a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should be noted that, in other implementations, the function(s) noted in the blocks may occur out of the order noted in the Figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending on the functionality involved.

The computer program instructions may be provided to a processor of a general purpose computer, a special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart and/or block diagram block or blocks. The computer program instructions may also be stored in a non-transitory computer usable or computer-readable memory that may direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer usable or computer-readable memory produce an article of manufacture including instructions that implement the function specified in the flowchart and/or block diagram block or blocks.

Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, the present specification, including the drawings, shall be construed to constitute a complete written description of all combinations and subcombinations of the embodiments described herein, and of the manner and process of making and using them, and shall support claims to any such combination or subcombination.

The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. The invention is defined by the following claims, with equivalents of the claims to be included therein. 

That which is claimed:
 1. A vacuum sealer apparatus, comprising: a housing comprising a vacuum chamber therein; a vacuum pump in fluid communication with the vacuum chamber; a sealing mechanism adjacent a periphery of the vacuum chamber; and at least one processor that is configured to execute program code stored in a non-transitory computer readable storage medium to perform operations comprising: calculating a rate of change of a vacuum level in the vacuum chamber responsive to energizing the vacuum pump to withdraw air from the vacuum chamber; and energizing the sealing mechanism based on the rate of change of the vacuum level.
 2. The vacuum sealer apparatus of claim 1, wherein the operations further comprise: reducing power to the vacuum pump based on the rate of change of the vacuum level.
 3. The vacuum sealer apparatus of claim 2, wherein the operations further comprise: identifying a transition in the rate of change of the vacuum level, wherein the energizing the sealing mechanism and/or the reducing the power to the vacuum pump is responsive to identifying the transition.
 4. The vacuum sealer apparatus of claim 3, wherein the transition in the rate of change of the vacuum level comprises a transition from a negative slope to a positive slope.
 5. The vacuum sealer apparatus of claim 4, wherein: calculating the rate of change of the vacuum level comprises generating vacuum level data based on a signal output from at least one sensor responsive to the energizing the vacuum pump, and identifying the transition comprises determining that a first rate of change between first samples of the vacuum level data is greater than a second rate of change between second samples of the vacuum level data.
 6. The vacuum sealer apparatus of claim 5, wherein the signal comprises a voltage signal, and wherein the at least one sensor comprises a pressure transducer that is in or mechanically coupled to the vacuum chamber.
 7. The vacuum sealer apparatus of claim 4, wherein the vacuum chamber is configured to receive an open end of a polymeric bag adjacent the periphery thereof, and wherein the transition in the rate of change of the vacuum level indicates substantial removal of air from the polymeric bag without substantial removal of fluid from the polymeric bag.
 8. The vacuum sealer apparatus of claim 7, wherein the sealing mechanism comprises at least one heating element adjacent the periphery of the vacuum chamber.
 9. The vacuum sealer apparatus of claim 5, wherein the operations further comprise: determining a baseline pressure for the vacuum chamber based on a signal output from the at least one sensor in a calibration process; and identifying a vacuum leak when the vacuum level does not reach the baseline pressure within a predetermined time after the energizing the vacuum pump.
 10. The vacuum sealer apparatus of claim 5, wherein the operations further comprise: determining an atmospheric pressure based on a signal output from the at least one sensor when the vacuum chamber is not sealed; and correcting the vacuum level data based on the atmospheric pressure.
 11. A method of operating a vacuum sealer apparatus, the method comprising: executing, by at least one processor of the vacuum sealer apparatus, program code stored in a non-transitory computer readable storage medium to perform operations comprising: calculating a rate of change of a vacuum level in a vacuum chamber having a vacuum pump in fluid communication therewith responsive to energizing the vacuum pump to withdraw air from the vacuum chamber; and energizing a sealing mechanism adjacent a periphery of the vacuum chamber based on the rate of change of the vacuum level.
 12. A method of claim 11, wherein the operations further comprise: reducing power to the vacuum pump based on the rate of change of the vacuum level.
 13. The method of claim 12, wherein the operations further comprise: identifying a transition in the rate of change of the vacuum level, wherein the energizing the sealing mechanism and/or the reducing the power to the vacuum pump is responsive to identifying the transition.
 14. The method of claim 13, wherein the transition in the rate of change of the vacuum level comprises a transition from a negative slope to a positive slope.
 15. The method of claim 14, wherein: calculating the rate of change of the vacuum level comprises generating vacuum level data based on a signal output from at least one sensor responsive to the energizing the vacuum pump, and identifying the transition comprises determining that a first rate of change between first samples of the vacuum level data is greater than a second rate of change between second samples of the vacuum level data.
 16. The method of claim 15, wherein the signal comprises a voltage signal, and wherein the at least one sensor comprises a pressure transducer that is in or mechanically coupled to the vacuum chamber.
 17. The method of claim 14, wherein the vacuum chamber is configured to receive an open end of a polymeric bag adjacent the periphery thereof, and wherein the transition in the rate of change of the vacuum level indicates substantial removal of air from the polymeric bag without substantial removal of fluid from the polymeric bag.
 18. The method of claim 15, wherein the operations further comprise: determining a baseline pressure for the vacuum chamber based on a signal output from the at least one sensor in a calibration process; and identifying a vacuum leak when the vacuum level does not reach the baseline pressure within a predetermined time after the energizing the vacuum pump.
 19. The method of claim 15, wherein the operations further comprise: determining an atmospheric pressure based on a signal output from the at least one sensor when the vacuum chamber is not sealed; and correcting the vacuum level data based on the atmospheric pressure.
 20. A vacuum sealer apparatus, comprising: a housing comprising a vacuum chamber therein, wherein the vacuum chamber is configured to receive an open end of a polymeric bag adjacent a periphery thereof; a vacuum pump in fluid communication with the vacuum chamber; a sealing mechanism comprising at least one heating element adjacent the periphery of the vacuum chamber; and at least one processor that is configured to execute program code stored in a non-transitory computer readable storage medium to perform operations comprising: calculating a rate of change of a vacuum level in the vacuum chamber responsive to energizing the vacuum pump to withdraw air from the vacuum chamber; identifying a transition in the rate of change of the vacuum level in the vacuum chamber, wherein the transition indicates substantial removal of air from the polymeric bag without substantial removal of fluid from the polymeric bag; and energizing the at least one heating element and reducing power to the vacuum pump responsive to identifying the transition in the rate of change of the vacuum level. 